%0 Journal Article
%T Total $¦Ã^*$ p Cross Section
%A E. Gotsman
%A E. Levin
%A U. Maor
%A E. Naftali
%J Physics
%D 1999
%I arXiv
%R 10.1007/s100520050607
%X This paper shows that the approach based on Gribov's ideas for the photon-proton interaction, is able to describe the experimental data over a wide range of photon virtualities $Q^2 = 0 - 100 GeV^2$ and energies $\sqrt{s} = W = 3 - 300 GeV$. A simple model is suggested which provides a quantitative way of describing the matching between short and long distances (between "soft" and "hard" processes) in photon-proton interaction at high energy. The main results of our analysis are: (i) the values of the separation parameters differentiating the "soft" and "hard" interactions are determined; (ii) the additive quark model can be used to calculate the "soft" contribution to the photon - proton interaction; (iii) a good description of the ratio $\sigma_L/\sigma_T$ is obtained ; and (iv) a considerable contribution of the "soft" process at large $Q^2$, and of "hard" processes at small $Q^2$ was found.
%U http://arxiv.org/abs/hep-ph/9904277v1